1. Field of the Invention
The present invention relates to a sliding component used as a timepiece component such as a cogwheel or a bearing.
2. Background Information
As a method of manufacturing a sliding component of high dimensional precision such as a small cogwheel, there is employed a technique combining photolithography and electroforming (See, for example, Patent Document 1). A sliding component involves generation of friction due to a mutual action between itself and a component held in contact therewith. If the regions of these components in contact with each other lack wear resistance, these components will be worn early. The efficiency of a mechanism using the sliding component is markedly affected by wear. In view of this, in order to achieve an increase in wear resistance, a lubricating oil is used. However, being a liquid, the lubricating oil does not remain at the sliding portion but there is danger of its being dispersed over the entire sliding component or to other components. In view of this, some sliding components adopt a structure which retains the lubricating oil at the sliding portion (See, for example, Patent Document 2).    Patent Document 1: JP-A-2006-64575    Patent Document 2: JP-T-2007-506073
In the structure disclosed in Patent Document 1, the sliding portion is smooth, so that any lubricating oil used does not remain at the sliding portion but is quite likely to be dispersed.
The structure disclosed in Patent Document 2 adopts a lubricating oil retaining structure, so that the possibility of the lubricating oil being dispersed is low. FIG. 31 is a partial sectional view showing a sliding process between an escape tooth 501 of an escape wheel & pinion and a pallet 210 of a pallet fork constituting the mating component as disclosed in Patent Document 2.
The escape tooth 501 retains a lubricating oil 410 at a lubricating oil retaining portion 521, so that the lubricating oil 410 is not dispersed but remains at the sliding portion. As shown in FIGS. 31(a) and 31(d), when the escape tooth 501 and the pallet 210 are held in contact with each other in a straight state, the lubricating oil 410 is supplied to the sliding portion, so that lubrication property is to be expected.
Also in a case in which the escape tooth 501 and the pallet 210 are held in contact with each other while inclined as shown in FIGS. 31(b) and 31(e), the lubricating oil 410 is supplied to the sliding portion, so that lubrication property is to be expected. However, in a case in which the escape tooth 501 and the pallet 210 are held in contact with each other while inclined as shown in FIGS. 31(c) and 31(f), there is a possibility of the lubricating oil 410 not being supplied from the lubricating oil retaining portion 521.